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SCIENTIFIC  ABSTRACTING 


By  Gordon  S.   Fulcher 
Corning  Glass  Works 


Published  in  Science 
September  30,  192 1,  Vol,  LIV,  No.  1396,  Pages  291-295 


Announcement  Concerning  Publications 

of  the 

National  Research  Council 


The  Proceedings  of  the  National  Academy  of  Sciences 

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Council 

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[Reprinted  from  SCIENCE,  N.  S.,    Vol.  LIV.,   No. 
1396,  Pages  291-295,  Sept.  30,  19S1] 


SCIENTIFIC  ABSTRACTING^ 

7s  it  worth  while  for  scientific  journals  to 
provide  abstracts  at  the  beginning  of  their 
articles? 

The  answer  to  this  question  depends,  of 
course,  on  the  nature  of  the  abstracts.  If  they 
are  sketchy,  incomplete  and  unreliable,  as 
many  abstracts  published  at  present  are,  they 
may  be  worse  than  useless.  But  suppose  each 
abstract  describes  the  contents  of  the  article 
so  completely  and  precisely  that  any  reader  can 
tell  with  assurance  whether  the  article  contains 
any  results  of  interest  to  him,  and  suppose  it 
summarizes  the  methods,  conclusions  and 
theories  so  as  to  give  all  the  information  any 
reader  not  a  specialist  in  the  narrow  field  in- 
volved needs;  that  is,  suppose  each  is  the 
result  of  a  careful  analysis  of  the  article  by  a 
competent  abstractor,  would  not  such  abstracts 
enable  the  reader  to  grasp  the  significant  re- 
sults in  the  articles  not  only  more  quickly  but 
more  completely  and  clearly  than  by  skim- 
ming through  the  articles? 

Such  abstracts  would  save  much  time  for 
the  scientist  not  only  as  a  reader  of  current 
literature  but  also  as  an  investigator.  For 
when  he  desires  information  on  a  certain  nar- 
row subject,  such  abstracts  would  help  him  to 
determine  more  quickly  than  otherwise  which 
of  the  articles  referred  to  in  a  bibliography  or 
other  list  contain  what  he  needs;  and  fre- 
quently the  abstracts  would  give  him  the  in- 
formation directly  and  make  a  search  through 
the   articles  unnecessary.      Finally,    such   ab- 

1  The  method  of  analytic  abstracting  described 
in  this  paper  was  developed  by  the  writer  during 
1919-20  while  on  the  staff  of  the  Eesearch  In- 
formation Service  of  the  National  Eesearch 
Council. 


stracts  would  save  his  time  as  an  abstractor 
at  home  and  abroad.  For  abstract  journals 
are  recognized  to  be  such  useful,  almost  in- 
dispensable guides  to  scientific  literature  that 
most  sciences  have  one  or  more  in  each  of  the 
great  scientific  languages.  At  present,  then, 
most  of  the  articles  in  the  fields  of  astronomy, 
physics,  chemistry,  biology,  and  medicine  are 
abstracted  from  three  to  six  times  each,  while 
if  an  abstract  suitable  for  reprinting  in  an  ab- 
stract journal  were  prefixed  to  each  original 
article,  a  reabstracting  of  the  article  would 
be  unnecessary  and  much  duplication  of  effort 
would  be  avoided.  Moreover  the  practise  would 
enable  abstract  journals  to  report  current  lit- 
erature with  less  delay  than  at  present. 

But  to  render  this  service  to  scientists,  the 
abstracts  must,  as  stated  above,  adequately  de- 
scribe and  summarize  the  contents  of  the 
articles.  The  standard  must  not  only  be 
high;  it  must  be  uniform,  so  that  the  ab- 
stracts may  be  beyond  suspicion  of  incomplete- 
ness and  inaccuracy. 

During  1920  the  ISTational  Eesearch  Council 
devoted  considerable  attention  to  various  ques- 
tions relating  to  abstracts,  such  as:  how  they 
might  be  improved  in  form  so  as  to  render 
more  effective  service;  how  the  rules  might 
be  made  more  definite  and  the  method  of  prep- 
aration more  systematic  so  as  to  result  in 
more  uniformly  good  abstracts.  As  a  result 
of  study  and  experimentation  a  type  of  ab- 
stract was  developed  which  is  believed  to  be 
well  suited  to  the  needs  both  of  abstract  jour- 
nals and  of  scientific  journals  with  prelimi- 
nary abstracts. 

Abstracts  of  this  type;  which  are  called 
analytic  abstracts,  have  been  appearing  in  the 
Astrophy steal  Journal  and,  less  consistently,  in 
the  Physical  Review  since  January,  1920. 
Their  main  characteristics  are  illustrated  in 
the  following  samples. 


1.  A  new  method  of  determining  the  atomic 

weight  of  iodine.    Marcel  Guichard ;  Ann. 
chim.,  6,  279-318  (1916);   7,  5-49  (1917). 

ABSTRACT 

Atomic  weight  of  iodine. — The  pentoxide 
method  used  involves  the  preparation  of  l20g, 
the  decomposition  of  this  anhydrid,  and  the 
collection  of  the  iodine  by  condensation  and  of 
the  oxygen  by  combination  with  pure  copper. 
The  mean  of  five  determinations  is  126.915. 
The  article  gives  in  voluminous  detail  the  re- 
finements  employed   to   guard   against   error. 

Iodine  pentoxide;  preparation,  purification 
and  decomposition  with  heat. — The  results  of 
a  thorough  study  are  presented.  As  it  was 
found  impracticable  to  prepare  it  by  direct 
combination  of  1^  and  O,,  the  method  adopted 
was  to  oxidize  I2  with  fuming  HlSTOg  and 
subsequently  expel  free  I^  and  HNOj  by 
heating  to  450°.  This  was  carried  out  in  an 
evacuated  train  which  is  fully  described. 

Preparation  of  pure  iodine. — Detailed  di- 
rections are  given. 

Occlusion  of  oxygen  hy  glass,  porcelain  and 
copper  was  studied  in  order  to  determine  the 
best  material  for  the  apparatus. 

2.  On  K.  S.  magnet  steel.    K.  Honda  and  S. 

Saito;  Physical  Review,  16,  495-500,  De- 
cember, 1920. 

ABSTRACT 

K.  8.  magnet  steel  (0  0.^-0.8,  Co  30-^0, 
W  5-9,  Cr  1.5-3  per  cent). — This  remarkable 
new  alloy  steel  possesses,  when  tempered,  an 
extremely  high  coercive  force,  226-257  gauss, 
and  a  strong  residual  magnetism,  varying  from 
620  to  920  C.G.S.  units  for  different  specimens. 
The  effect  of  repeated  shock  was  to  reduce 
these  values  by  only  6  per  cent.    The  hysteresis 


curves  for  a  magnetizing  force  of  =b  1300 
gauss  show  for  the  hardened  steel  an  energy 
loss  of  900,000  ergs  per  cycle.  Tempering  is 
best  effected  by  heating  to  950°  C.  and  quench- 
ing in  heavy  oil.  This  treatment  applied  to 
annealed  specimens  increases  the  Brinell 
hardness  number  from  444  to  652  and  makes 
the  microstructure  finer  grained. 

3.  The  structure  of  the  helium  atom.  Irving 
Langmuir;  Physical  Review,  17,  339-353, 
March,  1921. 

ABSTRACT 

Helium  atom  models. — (1)  Bohr's  model  is 
unsatisfactory  because  it  gives  too  great  a 
value  for  the  ionizing  potential  and  is  not  in 
accord  with  some  of  the  optical  and  mag- 
netic properties  of  helium.  Since  the  chem- 
ical evidence  suggests  that  each  electron  in 
an  atom  has  its  own  orbit,  separated  from  the 
other  orbits  but  closely  interrelated  with  them, 
two  new  models  are  considered.  (2)  In  the 
double  circle  model  the  two  electrons  are  as- 
sumed to  move  in  two  circular  orbits,  separate 
but  parallel.  This  model,  however,  is  unstable, 
for  the  ionizing  potential  computed  by  apply- 
ing the  quantum  theory,  comes  out  negative. 
Another  objection  to  this  model  is  that  the 
magnetic  moment  is  not  zero.  (3)  In  the 
semi-circular  model  each  electron  is  assumed 
to  oscillate  back  and  forth  along  an  approxi- 
mately semi-circular  path  in  accordance  with 
classical  mechanics,  each  being  brought  to 
rest  at  each  end  of  its  path  by  the  repulsion 
of  the  other.  Assuming  the  maximum  angu- 
lar momentum  of  each  electron  equal  to  h/27r 
the  absolute  dimensions  come  out  such  as  to 
give  a  total  energy  0.9618  times  that  of  the 
Bohr  model,  and  the  computed  ionizing  po- 
tential, 25.62  volts,  agrees  closely  with  the 
experimental  value.  The  magnetic  moment  is 
zero. 


Application  of  the  quantum  theory  to 
coupled  electrons. — The  success  of  the  semi- 
circular model  of  helium  suggests  that  in  the 
case  of  coupled  electrons  the  quantum  theory- 
should  be  applied  not  to  the  momentum  of  the 
individual  electrons  according  to  the  relation 
fpdq  =  h/2Tr,  but  rather  to  the  momentum 
which  by  being  relayed  from  one  electron  to 
another,  passes  in  each  direction  around  the 
nucleus. 

4.  Studies  on  inbreeding.  IV.  Effects  of  in- 
breeding on  the  growth  and  variability  in 
body  weight  of  the  albino  rat.  .Helen  D. 
King;  Jour.  Exp.  Zool.,  29,  No.  1  (1919). 

ABSTRACT 

Effects  of  inbreeding  on  the  growth  and 
variability  in  body  weight  of  the  albino  rat. — 
In  continuation  of  previous  work,  data  are 
given  concerning  over  600  rats  belonging  to 
the  sixteenth  to  twenty-fifth  generations  of  a 
strain  bred  brother  to  sister  from  the  same 
litter  only.  Allowing  for  the  effect  of  certain 
unfavorable  conditions,  determined  by  control 
rats,  the  results  confirm  previous  conclusions 
and  show  that  close  inbreeding  continued  for 
25  generations  has  not  produced  any  deteriora- 
tion in  the  stock  as  regards  the  growth  curve, 
the  body  weight,  the  variability  of  body  weight 
for  various  ages,  and  the  relative  behavior  of 
the  sexes  in  these  respects.  Selected  rats  were 
used  as  the  parents  of  each  generation.  If 
there  is  any  tendency  to  deterioration  it  was 
counteracted  in  these  experiments  by  the  se- 
lection employed. 

Effect  of  nutrition  on  the  growth  and  varia- 
bility in  body  weight  of  the  albino  rat. — Rats 
are  particularly  sensitive  to  food  conditions. 
Alfalfa,  cottonseed  and  linseed  meal  were 
found  to  be  injurious.  A  change  from  a  satis- 
factory diet  to  one  less  suitable  resulted  in  a 


marked  increase  in  variability  of  body  weight 
both  for  inbred  and  stock  rats. 

Sex  ratio  in  the  albino  rat. — By  selection 
the  inbred  strain  has  been  separated  into  two 
lines,  one  with  a  high,  the  other  with  a  low, 
sex  ratio;  but  the  ejfect  of  selection  seems  to 
be  limited.  The  two  strains  are  alike  in  body 
weight,  growth  curve  and  variability  of  body 
weight. 

It  will  be  noticed  that  each  of  the  one  or 
more  paragraphs  of  each  abstract  begins  with 
an  italicized  paragraph  title.  In  some  cases 
words  or  phrases  within  a  paragraph  are  also 
italicized.  This  is  not  done  for  emphasis  but 
to  associate  them  with  the  paragraph  titles 
which  they  supplement  and  complete.  Para- 
graph titles  and  italicized  words  and  phrases 
will  collectively  be  called  subtitles.  If  the 
reader  will  run  through  the  sample  abstracts, 
skipping  all  but  these  italicized  subtitles,  he 
will  get  in  each  case  a  descriptive  index  of 
the  information  in  the  article.     For  example: 

ABSTRACT    NO.    1 

Atomic  weight  of  iodine. 

Pentoxide  method. 

Determinations. 
Iodine  pentoxide. 

Preparation,  purification. 

Decomposition  with  heat. 
Preparation  of  pure  iodine. 
Occlusion  of  oxygen  by  glass,  porcelain  and 

copper. 

ABSTRACT     NO.     3 

Helium  atom  models. 

(1)  Bohr's  model. 

(2)  Double  circle  model. 

(3)  Semi-circular  model. 
Application     of     the     quantum     theory     to- 
coupled   electrons;  suggestion. 

The  subtitles,  then,  form  in  each  case  an 
index  of  the  abstract.     By  glancing  through 


them  a  reader  can  tell  with  assurance  whether 
the  article  deals  with  anything  of  interest  to 
him.  It  is  well  known  that  one  can  not  rely 
upon  the  author's  title  alone,  for  many  articles 
contain  incidental  information  or  a  variety 
of  information  which  a  short  title  can  not 
fully  describe.  The  first  and  last  articles  ab- 
stracted above  are  good  instances  of  this  fact. 
On  the  other  hand,  the  subtitles  of  this  type 
of  abstract,  since  they  may  be  as  numerous 
as  is  necessary,  can  give  in  all  cases  the  pre- 
cise scope  of  the  information  contained  in  the 
article;  in  particular  they  can  call  attention 
to  incidental  results  whose  presence  would  not 
be  suspected  from  the  title,  such  as  the  data 
relating  to  the  occlusion  of  oxygen  given  in 
the  article  on  the  atomic  weight  of  iodine. 

Besides  providing  a  complete  index  in  the 
form  of  subtitles,  the  abstracts  are  required 
to  describe  the  new  information  with  sufficient 
precision  and  to  summarize  the  results  with 
sufficient  completeness  and  in  sufficient  de- 
tail to  satisfy  the  needs  of  the  great  majority 
of  readers.  Each  abstract  should  be  a  care- 
fully prepared  report  on  the  contributions  to 
scientific  knowledge  set  forth  in  the  article,  by 
a  scientist  who  feels  his  responsibility  to  his 
scientific  colleagues  to  make  it  complete  and 
accurate. 

But  why  go  to  the  trouble  of  preparing  such 
abstracts?  Why  not  let  each  reader  glance 
through  each  article  and  determine  what  it 
contains  for  himself  ?  Because  for  each  scien- 
tist to  do  his  own  abstracting,  as  this  would 
amount  to,  is  as  wasteful  as  for  each  to  pre- 
pare his  own  indexes  of  the  reference  books 
he  uses ;  it  means  not  only  an  unnecessary  du- 
plication of  effort  but,  worse  still,  a  poor 
quality  of  abstracting,  in  most  cases.  Then 
there  is  to  be  considered  the  waste  involved  in 
the  simultaneous  abstracting  of  each  article  by 


8 


several  abstract  journals.  Efficiency  demands 
that  a  good  preliminary  abstract  be  provided 
with  each  article,  so  that  all  readers  may  bene- 
fit by  the  careful  work  of  one  abstracter  and 
none  need  abstract  that  article  again. 

Anyone  may  readily  convince  himself  of 
the  value  of  preliminary  analytic  abstracts  if 
he  will  turn  to  one  of  the  longer  articles  in 
the  Astro -physical  Journal  since  January,  1920, 
and,  after  spending  three  to  five  minutes  in 
abstracting  the  article  for  himself  by  glancing 
through  it,  will  compare  the  information  he 
thus  gains  with  what  he  might  have  obtained 
in  an  equal  time  from  the  abstract. 

There  can  be  no  doubt,  then,  that  good  pre- 
liminary abstracts  would  save  much  time  for 
scientists  as  readers,  investigators  and  ab- 
stractors. But  is  this  of  any  importance? 
Before  the  war  many  would  have  said.  No. 
Research  was  generally  regarded  as  a  hobby. 
Now  it  is  more  generally  realized  that  the 
research  output  of  the  country  is  a  matter  of 
national  concern  and  is  an  important  factor 
in  national  progress. 

The  number  of  scientists  actively  engaged 
in  research  work  is  relatively  small.  Their 
research  time  is  correspondingly  valuable,  es- 
pecially as  it  is  further  limited  by  the  fact 
that  most  of  them  have  teaching  or  executive 
duties  which  take  much  of  their  energy.  Of 
this  time  the  larger  the  part  devoted  to  se- 
curing the  necessary  foundation  of  scientific 
information,  both  current  and  past,  the  less 
the  part  available  for  actual  research.  There- 
fore, everything  possible  should  be  done  to 
make  it  as  easy  as  practicable  for  each  inves- 
tigator to  obtain  the  information  he  needs; 
that  is,  our  whole  scientific  information  serv- 
ice, including  original  scientific  journals,  ab- 
stract journals,  handbooks,  tables,  etc.,  should 
be  made  in  its  parts  and  as  a  whole,  as  efficient 
as  possible.     All  this  is  self-evident.     In  this 


9 

note  we  are  considering  merely  the  scientific 
journals.  Their  part  is  to  provide  preliminary 
abstracts.  And  since  this  can  be  done  at  very 
small  additional  expense  to  each  and  since  the 
saving  of  time  for  scientists  would  be  in  the 
aggregate  considerable,  surely  there  can  be 
no  question  as  to  the  advisability  of  the  adop- 
tion of  this  policy  by  every  scientific  journal. 

Wliat  obstacles  stand  in  the  way?  The  ad- 
ditional expense  is,  as  just  stated,  small.  The 
abstract  would  be  less  than  five  per  cent  of 
the  article  on  the  average,  and  if  the  sum- 
mary usually  placed  at  the  end  were  omitted, 
as  could  well  be  done  because  its  function 
would  be  served  by  the  abstract,  the  increase 
in  length  of  the  article  would  be  little  or  noth- 
ing. But,  on  the  other  hand,  the  addition  of 
abstracts  would  undoubtedly  considerably  in- 
crease the  burdens  of  the  already  overburdened 
editors,  and  one  would  shrink  from  suggesting 
that  they  add  to  their  labors  the  drudgery  as- 
sociated with  securing  and  editing  the  ab- 
stracts if  it  were  not  clear  that  the  gain  to  the 
many  investigators  would  be  many  times  the 
cost  to  the  few. 

At  present,  in  addition  to  the  Astrophysical 
Journal,  Physical  Review,  and  Journal  of  the 
American  Ceramic  Society,  which  require  ana- 
lytic abstracts,  the  following  fourteen  scien- 
tific and  engineering  journals  give  preliminary 
abstracts:  The  group  of  biological  journals 
published  by  the  Wistar  Institute  of  Anatomy 
and  Biology — American  Journal  of  Anatomy, 
American  Anatomical  Memoirs,  Anatomical 
Record,  Journal  of  Comparative  Neurology, 
Journal  of  ExpeAmental  Zoology,  and  Journal 
of  Morphology;  also  Physiological  Researches; 
Proc.  of  London  Physical  Society,  Trans,  of 
American  Electrochemical  Society,  Trans,  of 
American  Institute  of  Electrical  Engineers, 
Trans,  of  American  Society  of  Civil  Engineers, 
Trans,  of  American  Society  of  Mechanical  En- 


10 


gineers,  Trans,  of  Society  of  Automotive  Engi- 
neers, and  Trans,  of  American  Foundrymen's 
Association.  The  abstracts  now  being  provided 
by  these  journals  are  prepared  as  a  rule  by  the 
authors  and  vary  greatly  in  quality.  It  would 
be  relatively  easy  for  those  journals  whose  ab- 
stracts are  not  as  useful  as  is  desirable  to 
change  their  rules  so  as  to  require  abstracts  of 
the  quality  of  analytic  abstracts. 

The  directions  and  rules  which  have  been 
formulated  for  the  guidance  of  authors  in  the 
preparation  of  analytic  abstracts  may  be  found 
in  current  numbers  of  the  Astrophysical  Jour- 
nal and  also,  somewhat  abbreviated,  in  those 
of  the  Physical  Review  and  of  the  Journal  of 
the  American  Ceramic  Society.  With  slight 
modification  they  would  serve  for  any  science. 
But  while  some  authors  will  take  the  trouble 
to  master  the  technique  and  prepare  satisfac- 
tory abstracts,  a  uniformly  high  standard  can 
not  be  maintained  im.less  all  the  abstracts  for 
each  journal  are  checked  and  revised  by  a 
competent  abstractor.  Therefore,  after  decid- 
ing to  require  analytic  abstracts,  the  first 
step  taken  by  a  journal  should  be  the  selec- 
tion of  a  suitable  man  as  abstract  editor.  If 
the  man  appointed  should  care  to  get  in  touch 
with  me,  I  should  be  glad  to  give  any  assis- 
tance I  can  in  getting  the  new  policy  started. 

In  conclusion,  attention  should  be  directed 
to  the  fact  that  those  journals  which  provide 
analytic  abstracts  may  easily  combine  an  in- 
dex of  the  subtitles  in  the  abstracts  with  the 
usual  index  of  author's  titles,  and  thus  greatly 
increase  the  completeness  and  precision  of 
their  subject  -indexes  and  hence  the  value  of 
the  journal  for  reference  purposes. 

It  may  not  seem  of  much  importance  whe- 
ther any  particular  journal  provides  efficient 
abstracts  or  not.  Yet  it  is  clearly  the  duty  of 
each  to  do  so.  For  when  all  have  adopted  this 
policy    and    the    abstract    journals    promptly 


11 


reprint  all  the  abstracts  and  completely  index 
them,  we  shall  have  gone  far  toward  making 
our  scientific  information  service  really  effi- 
cient. And  because  of  the  cooperation  in- 
volved, it  will  require  less  effort  to  maintain 
than  our  present  much  less  efficient  service. 

SUGGESTIONS  AND  RULES  FOR  PREPARING 
ANALYTIC   ABSTRACTS 

The  preparation  of  an  abstract  naturally 
proceeds  in  four  steps,  as  follows : 

1.  Xotes. — First  I  read  the  article  carefully, 
making  notes  covering  all  the  new  information 
which  I  find  in  it,  keeping  an  especially  sharp 
lookout  for  new  incidental  results  or  sugges- 
tions not  directly  related  to  the  main  subject 
of  the  paper.  These  notes  are  rough  and  in- 
tended merely  as  memory  aids.  If  this  search 
is  not  thorough,  the  abstract  will  probably  be 
incomplete. 

ErLE  1.  Material  not  new  need  not  be  analyzed 
or  described;  a  valuable  summary  of  previous  work, 
however,  should  be  noted  with  a  statement  indicat- 
ing its  nature  and  scope. 

2.  Suh titles. — 'Next  comes  the  analysis  of 
the  information  and  the  formulation  of  the 
subtitles.  I  ask  myself  to  what  subject  do  the 
main  results  of  the  article  relate.  Perhaps  it 
is  "  the  atomic  weight  of  iodine."  Are  all 
phases  of  this  subject  included  or  only  cer- 
tain ones?  In  this  case  a  new  method  of  de- 
termination is  described  and  also  a  series  of 
experimental  results  obtained  by  that  method. 
Therefore  I  make  the  subtitle  more  precise  by 
adding  the  necessary  phrases,  in  this  case 
"  pentoxide  method  "  and  "  determinations." 
This  disposes  of'  the  main  subject.  But  are 
there  any  results  which  do  not  belong  under 
the  main  subtitle  ?  If  so,  to  what  subject  or 
subjects  do  they  relate?  I  write  them  down: 
"  Iodine  pentoxide  " ;  "  Occlusion  of  oxygen 
by  glass,  etc.,"  or  whatever  they  may  be,  and 


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I  add  any  modifying  phrases  necessary  to  make 
these  subtitles  precise.  The  analysis,  then, 
consists  merely  in  sorting  the  details  of  in- 
formation into  as  many  groups  as  there  are 
distinct  subjects  involved.  Then  for  each 
group,  the  scope  of  the  information  included 
is  determined  and  a  subtitle  is  written  just 
as  one  would  write  a  title  for  an  article  which 
contained  the  information  in  that  group.  Each 
subtitle  should  cover  all  the  details  in  its  group 
and  yet  should  not  imply  the  inclusion  of 
material  not  actually  contained;  that  is,  it 
should  be  both  complete  and  precise. 

Rule  2.  Each  subtitle  should  describe  the  corre- 
sponding information  so  precisely  that  the  chance 
of  any  investigator  being  misled  into  thinking  the 
article  contains  the  particular  information  he  de- 
sires when  it  does  not,  or  vice  versa,  may  be  small. 
"  Zeeman  effect  for  metallic  spectra  "  is  too  broad 
unless  all  metals  have  been  studied,  for  the  investi- 
gator may  be  interested  at  the  time  in  only  one 
metal;  but  "  Infra-red  arc  spectrum  of  iron  to 
3/(f  ' '  evidently  satisfies  the  rule.  In  general,  a  sub- 
title is  sufficiently  precise  if  it  carries  the  classi- 
fication of  the  information  involved  three  stages 
or  the  equivalent,  for  instance  if  it  gives  {a)  the 
elements  and  substances,  (6)  the  property,  and  (c) 
the  phase  or  range  studied. 

Rule  3.  The  subtitles  should  together  form  a 
complete  index  of  tJie  new  information;  that  is, 
they  should  include  every  measurement,  observa- 
tion, method,  suggestion  and  theory  which  is  pre- 
sented as  new  and  of  value  in  itself.  They  should 
be  complete  in  themselves  and  independent  of  the 
main  title  of  the  article. 

3.  Text. — Not  until  the  subtitles  are  formu- 
lated, do  I  proceed  to  the  writing  of  the  text 
of  the  abstract.  I  devote  a  paragraph  to  each 
group  of  details  beginning,  as  a  rule,  with 
those  relating  to  the  main  subject  of  the 
article.  In  case  several  phases  of  a  subject 
are  dealt  with  as  in  the  second  sample  abstract 
above,  it  is  often  convenient  to  begin  the  para- 


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graph  with  a  paragraph-title  which  merely 
gives  the  subject,  and  then  to  write  the  text 
in  such  a  way  as  to  bring  in  the  additional 
words  or  phrases  which  the  analysis  has  shown 
are  needed  as  additional  subtitles  to  indicate 
with  precision  the  information  involved.  When 
several  subtitles  are  coordinate,  as,  for  in- 
stance, in  the  third  sample  abstract  above,  I 
call  attention  to  this  fact,  when  it  can  be  done 
conveniently,  by  numbering  them.  The  main 
thing,  however,  besides  seeing  that  the  neces- 
sary subtitles  are  included,  is  to  make  the  ab- 
stract as  informing  as  practicable.  It  should 
never  be  merely  a  sketch  of  the  scope  of  the 
article  unless  this  contains  no  new  informa- 
tion. 

EuLE  4.  A  separate  paragraph  should  be  used 
for  each  distinct  subject  involved,  but  no  more 
paragraphs  than  necessary.  All  material  which  can 
easily  be  grouped  together  under  a  single  title 
should  be  summarized  in  the  same  paragraph. 
Parts  of  subtitles  may  be  scattered  through  the 
text  but  the  subject  of  each  paragraph  must  be 
given  at  the  beginning.  Underscore  subtitles  but 
no  other  words  or  phrases. 

Rule  5.  The  text  should  summarize  the  author's 
conclusions  and  should  transcribe  all  numerical  re- 
sults of  general  interest  including  all  that  might 
be  looked  for  in  a  table  of  physical  and  chemical 
constants.  It  should  give  all  the  information  that 
any  one,  not  a  specialist  in  the  narrow  field  in- 
volved, might  care  to  have  in  his  notebook. 

Rule  6.  Complete  sentences  should  be  used  ex- 
cept in  the  case  of  subtitles.  The  abstract  should 
be  made  as  readable  as  the  necessary  brevity  will 
permit. 

As  to  what  should  constitute  a  group  and 
how  many  groups  should  be  made,  rules  can 
not  be  given  which  will  cover  all  cases.  Since 
abstracts  should  be  as  unified  as  is  practicable 
without  defeating  the  purpose  of  the  abstract, 
it  is  my  policy  to  group  together  as  much  as 


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can  be  put  comfortably  under  a  single  para- 
graph title.  In  the  samples  above,  for  instance, 
all  the  properties  of  K.  S.  magnet  steel  are 
put  in  a  single  paragraph,  and  the  data  regard- 
ing the  preparation,  purification  and  decom]X)- 
sition  of  iodine  pentoxide  by  heat  are  grouped 
together.  But  "  the  preparation  of  pure 
iodine  "  could  not  conveniently  be  combined 
with  "  atomic  weight  of  iodine,"  at  least  with- 
out blurring  the  emphasis  on  the  main  con- 
tribution of  the  paper ;  and  for  similar  reasons 
I  have  separated  "  the  effect  of  nutrition  on 
the  growth  of  the  albino  rat  "  from  "  the  effects 
of  inbreeding  on  the  growth  of  the  albino  rat." 
The  tendency  of  beginners  seems  to  be  to  make 
too  many  groups  and  thus  to  chop  up  the  ab- 
stract unnecessarily.  However,  the  number  of 
groups  is  of  minor  importance  provided  all  the 
new  results  are  included  in  one  or  other. 

As  to  the  length  of  the  abstract,  brevity  is 
important,  and  useless  words  and  unimportant 
details  should  be  rigorously  pruned.  The  ab- 
stracts in  the  Asirophysical  Journal  contain 
on  the  average  one  twentieth  as  many  words 
as  the  article  abstracted.  Usually  the  propor- 
tion is  greater  for  short  articles  and  less  for 
longer,  but  of  course  it  depends  on  the  type 
of  article. 

4.  ChecMng  the  Abstract. — Finally  I  re-read 
the  article  in  order  to  check  the  abstract  and 
to  correct  any  omissions  or  mistakes;  I  read 
the  underscored  subtitles  by  themselves  to  see 
whether  they  properly  index  the  information; 
and  I  read  the  abstract  through  to  see  whether 
I  can  not  gain  in  brevity  without  losing  in 
clearness  or  improve  the  English  withovit  add- 
ing too  much  to  the  length.  By  combining  or 
rearranging  sentences,  it  is  frequently  possible 
to  make  a  series  of  condensed  statements  less 
disjointed. 

An  examination  of  the  series  of  abstracts 
in  the  Asirophysical  Journal  will  give  a  much 


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clearer  idea  of  the  form  and  character  of  an- 
alytic abstracts  than  a  set  of  rules.  Any 
author  who  will  take  the  trouble  to  make  such 
an  examination  and  who  will  follow  the  pro- 
cedure suggested  above,  particularly  in  the 
matter  of  formulating  adequate  subtitles  he- 
fore  writing  the  text,  should  have  little  diffi- 
culty in  preparing  satisfactory  abstracts. 

Gordon  S.  Fulcher 
Corning  Glass  Works, 
June  16,  1921 


562  693 


